Failure Modes and Effects Analysis for Hydrogen …

1 DOT HS 811 075 February 2009 Failure Modes and Effects Analysis for Hydrogen FuelCell Vehicles Subtask 1 Final Report This document is available to the public from the National Technical Information Service, Springfield, Virginia 22161 DISCLAIMER This publication is distributed by the Department of Transportation, National Highway Traffic Safety Administration, in the interest of information exchange. The opinions, findings, and conclusions expressed in this publication are those of the authors and not necessarily those of the Department of Transportation or the National Highway Traffic Safety Administration. The United States Government assumes no liability for its contents or use thereof. If trade names, manufacturers names, or specific products are mentioned, it is because they are considered essential to the object of the publication and should not be construed as an endorsement.

2 The United States Government does not endorse products or manufacturers. TECHNICAL REPORT DOCUMENTATION PAGE 1. Report No. DOT HS 811 075 2. Government Accession No. 3. Recipient's Catalog No. 4. Title and Subtitle Failure Modes and Effects Analysis for Hydrogen Fuel Cell Vehicles Subtask 1 5. Report Date February 2009 6. Performing Organization Code 7. Author(s) Denny R. Stephens, Susan E. Rose, Stephanie A. Flamberg, Stephen M. Ricci, and Paul E. George II 8. Performing Organization Report No. 9. Performing Organization Name and Address Battelle Memorial Institute 505 King Ave Columbus, OH 43201 10. Work Unit No. (TRAIS) 11. Contract or Grant No. DTNH22-02-D-02104 12. Sponsoring Agency Name and Address National Highway Traffic Safety Administration 1200 New Jersey Avenue SE. Washington, DC 20590 13.

3 Type of Report and Period Covered Final 14. Sponsoring Agency Code Office of Applied Vehicle Safety Research Structures and Restraints Research Division, NVS-321 15. Supplementary Notes 16. Abstract Hydrogen fuel cell vehicles (HFCVs) offer the promise of significantly reducing the amount of pollutants expelled into the environment. However, the technology that is needed to store the Hydrogen fuel onboard and deliver it to the propulsion system is different from what consumers and even engineers currently know and understand. As an early step in identifying critical safety requirements for these vehicles and, if needed, developing appropriate Federal Motor Vehicle Safety Standards, the National Highway Traffic Safety Administration requested that Battelle undertake a high-level Failure Modes and Effects Analysis to characterize potential hazards from compressed- Hydrogen fuel cell vehicles and identify potential safety issues.

4 The objective of this effort is to review and assesses safety issues for Hydrogen vehicles and to identify areas that NHTSA may consider addressing in the FMVSS. The investigation found that, overall, the Failure Modes that appear to have the greatest hazard in Hydrogen vehicles are large releases of Hydrogen and rupture of the fuel container. The FMEA results show that if high-pressure components in compressed- Hydrogen fuel systems lack redundancy, a single-point Failure of the container, PRD, or first valve, can result in a large-scale release or venting of Hydrogen and, for containers, release of mechanical energy. Small releases of Hydrogen and rupture of other components may also be hazardous, but do not have the potential destructive force of large releases and fuel container rupture. 17. Key Words Hydrogen , fuel cell, compressed Hydrogen , fuel storage, FMEA, HFCV, risk, hazard 18.

5 Distribution Statement This report is free of charge from the NHTSA Web site at 19. Security Classif. (of this report) Unclassified 20. Security Classif. (of this page) Unclassified 21. No. of Pages 170 22. Price Form DOT F (8-72) Reproduction of completed page authorized Failure Modes and Effects Analysis February 2009 for Hydrogen Fuel Cell Vehicles i Final Report Failure Modes and Effects Analysis February 2009 for Hydrogen Fuel Cell Vehicles ii Final Report Page Executive Summary .. v Acronyms and Abbreviations .. vii 1 Project Objectives .. 1 Technical Approach .. 2 NHTSA and FMVSS 4 Elements of Compressed- Hydrogen Fuel Cell Vehicles .. 6 Hydrogen Fueling and Fuel Storage Subsystem .. 8 Hydrogen Fuel Delivery Subsystem .. 9 Fuel Cell Subsystem.

6 9 Electric Propulsion and Power Management 10 Unique Hazards of Compressed- Hydrogen Vehicles .. 11 Combustion Hazards .. 11 High-Pressure 14 Electrical Hazards .. 16 Crash 18 Fire Hazards .. 20 Failure Modes and Effects Analysis of Compressed- Hydrogen Fuel Cell Vehicle .. 21 Description of the FMEA Development 21 Description of the Results .. 24 Comparison of FMEA Results With Fuel Cell Vehicle Codes and 52 Review of Codes and Standards .. 52 Review of FMEA and Related Codes and Standards .. 53 Potential Gaps in Standards .. 72 Resulting Assessment of Safety 75 High-Consequence Failure 76 Root Causes and Design 77 Highly Variable 78 References .. 81 Appendix A: Summary of Hydrogen Vehicle Codes and Standards .. A-1 SAE Recommended A-1 ISO Safety Specifications.

7 A-8 CSA Draft A-13 Japanese HFCV Standard .. A-16 European Working A-19 Appendix B: Failure Modes and Effects Analysis of Compressed- Hydrogen Fuel Cell Vehicles With Codes and Standards .. B-1 TABLE OF CONTENTS Failure Modes and Effects Analysis February 2009 for Hydrogen Fuel Cell Vehicles iii Final Report Page List of Tables Table 1. Organization of FMVSS Standards ..5 Table 2. Comparative Transportation Fuel Table 3. HFCV Concept Model Systems, Subsystems, and Table 4. Likelihood Categories ..24 Table 5. Consequence Table 6. FMEA of Compressed- Hydrogen Fuel Cell Table 7. Overview of FCV Codes and 54 Table 8. Summary of Content of Compressed FCV Codes, Standards, and Analogous FMVSS .. 57 Table 9. Summary of HFCV FMEA and Codes and Standards ..61 List of Figures Figure 1.

8 High-Level Schematic of Compressed- Hydrogen Fuel Cell Vehicle Figure 2. Schematic of Compressed- Hydrogen Fuel Cell Vehicle Component Locations and Mass Figure 3. Comparison of Fuels on a Mass Energy Density Figure 4. Comparison of Fuels on a Volumetric Energy Density Basis ..15 Figure 5. Conventional Time/Current Zones of Effects of AC Currents (15 Hz to 100 Hz) on Persons for a Current Path Corresponding to Left Hand to Feet (Source: IEC 60479-1)..17 Figure 6. Conventional Time/Current Zones of Effects of DC Currents on Persons for a Longitudinal Upward Current Path (Source: IEC 60479-1)..18 Figure 7. Schematic of Compressed- Hydrogen Fuel Cell Vehicle Component Locations and Mass Figure 8. Simplified Diagram of Compressed- Hydrogen Fuel Cell Vehicle Figure 9. Risk Matrix ..24 TABLE OF CONTENTS (Continued) Failure Modes and Effects Analysis February 2009 for Hydrogen Fuel Cell Vehicles iv Final Report EXECUTIVE SUMMARY Hydrogen -fueled vehicles offer the promise of significantly reducing the amount of pollutants expelled into the environment.

9 However, the technology that is needed to store the Hydrogen fuel onboard and deliver it to the propulsion system is different from what consumers and even engineers currently know and understand. As an early step in identifying critical safety requirements for these vehicles and, if needed, develop appropriate Federal Motor Vehicle Safety Standards, the National Highway Traffic Safety Administration requested that Battelle undertake a high-level Failure Modes and Effects Analysis to characterize potential hazards from compressed- Hydrogen fuel cell vehicles and identify potential safety issues. The objective of the effort reported here is to review and assesses safety issues for Hydrogen vehicles and to identify areas that NHTSA may consider addressing in the FMVSS. Along with NHTSA, other government and industrial organizations are looking closely at Hydrogen vehicle safety needs and are developing standards for Hydrogen vehicle components, integrated subsystems (fuel storage and delivery, electrical, etc.)

10 And fully integrated Hydrogen vehicles. It is expected that NHTSA will not need to duplicate the work that is being done elsewhere to address safety of Hydrogen vehicles. Consequently, Battelle has focused this assessment on two fundamental questions: In its regulatory function, what safety issues should NHTSA consider prioritizing for compressed- Hydrogen vehicles? Are there potential gaps in the coverage of safety standards for compressed- Hydrogen vehicles that merit NHTSA s consideration? To address these challenging questions, Battelle adopted a structured approach that included the following activities. Review of NHTSA s safety objectives and the general topics addressed by the FMVSS to characterize NHTSA s potential roles in Hydrogen safety; Review of the unique elements of compressed- Hydrogen vehicles in an effort to narrow the scope of the assessment to those elements that are unique to Hydrogen vehicles; Review of the unique hazards of compressed- Hydrogen vehicles; Failure Modes and Effects Analysis of a conceptual compressed- Hydrogen fuel cell vehicle to characterize potential hazards and potential controls to mitigate these hazards; and Comparison of the results of the FMEA with fuel cell vehicle codes and standards to identify potential gaps in safety coverage that may need to be considered.